Jesse c



J. 0. KING.

ELECTRODE.

APPLSCATION man 0019,1911.

1 ,3 1 2,260 Patented Aug. 5, 1919.

y-kvrenl'or Jesse C, m

' tional area and consequently altering the resistance and conductivityof the electrode.

i JESSE C. KING, OF IAIONTREAL, QUEBEC, CANADA.

ELECTRODE Specification otjLetter s Patent. Patented Aug. 5, 1919.

Application filed October 9, 1917. Serial na'ie sms.

To all whom it may concern:

Be it known that I, JESSE C. KING, a citizen of theUnited States, and resident of the city of Montreal, in the Province of Quebec and Dominion of Canada, have invented certain new and useful Improvements in Electrodes, of which the following is a full, clear, and exact description.

This invention relates to improvements in electrodes for use in electric'furnaces and the like.

It is well known that electrodes which usually consist of carbon waste or burn away quite rapidly at points remote from the active end, thus reducing the efficiency and life of the electrode. The-carbon body becomes heated to very high temperatures for a considerable distance back from the end, and this heating renders the carbon more or less readily combinable withoxygen of the an or with other gases, with the result that the electrode burns away, thus reducing the sec- The main object ofmy invention is to provide an electrode having on the outer surface thereof a thin coating of non-oxidizing material designed to protect'the body of the electrode from combination with gases ation- I have found that a coating of finely ground bauxite is very suitable for this purpose, and the coating may be applied in the manner described in my copending application, Serial No. 99,104, filed May 22nd, 1916.

' ing a carbon core having a roughened sur- After the application of the protective coating, the electrode is preferably baked, so that the core and the coating become for all practical purposes integral.

Referring to the drawing, which represents a cross sectional view of the electrode with the coating applied thereto, 11 designates the core or electrode proper of carbon having the surface 12 roughened by any suitable means. The coating of bauxite 13 is then applied to the roughened surface,

' oughly hardened. at all parts of the surface not in actual operpreferabl in 'a plastic condition. The electrode 1st en baked to drive off the moisture and gases, and to harden boththe core and the coating. The bauxite which is ground to a suitable fineness may be molded, pasted, pressed or sprayed on to the roughened carbon core, and when suitably hardened, this coatlng forms an impenetrable coating between the electrode and the gases of the furnace. Kit is desired to mold the surface coating onto the carbon electrode,-the latter may be used in a suitable mold as a core and the surface coating may be pressed into the mold around the core in the usual manner. If the surface coating is to be pasted onto the core, a trowel or other suitable implement may be used and this surface coating in plastic condition may be pasted onto the roughened surface of the core, in as even a manner as possible. To spray'the coating onto the core, any suitableimplement such as a cement gun may be employed.

In some cases, it may be desirable to use a binder consisting of a small pro ortion of pitizh or other carbonaceous bon ing materia When i a' small quantity of such "a blnder s used, it holds the coating during the baking process where it becomes thor- Having thus described rhy'invention, what I claim is.:-

a 1. A coatin for electric furnace elec trodes, consistlng of finely ground bauxite and a carbonaceous blnder for same.

2. An electric furnace electrode comprisface, and a coating of bauxite bonded on to the roughened surface.

hand.

JESSE C. KING. 

